Film advance

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Glossary Terms

Film advance is a mechanism for moving film from one spool to another incrementally one frame at a time.

Advance may be a manual process, and may be called winding, advance, wind-on and various other terms, and may use, for example, a knob, key, lever, slider or thumbwheel. For this method there must be some way of stopping winding when the next frame is reached. Older cameras mostly use a red window, through which the user must watch for numbers printed on the film backing paper. Later cameras may have some more positive 'auto-stop' method where the camera has a roller or sprockets measuring the film to lock the winding at the correct point - or the film has a single hole locating the frame, as in 110 and 126 cartridge films.

Some cameras use more eccentric methods, such as the Werra, which has a ring around the lens for winding and the Voskhod and Agimatic - which have levers rotating around the lens, or the Bencini Unimatic, where the shutter release button is pushed sideways to wind, and the Voigtländer Vitessa and Welta Penti - equipped with plungers. The Calypso uses the wind-on lever for releasing the shutter as well.

In many cameras, the film advance process also cocks the shutter, and, frequently, releasing the shutter unlocks the film advance - providing double-exposure protection.

Falling Plate

A few plate cameras - magazine cameras - (e.g. the Houghton Klito No.1) adopted a "falling plate" arrangement, where a number of plates were kept in a sprung magazine, usually behind the focal plane. After exposure, the exposed plate fell forward and down into a well, allowing the next one to move forward for use.

A related system had a magazine of plates, but a sliding mechanism to move them to the focal plane and back. This was eventually evolved into the Polaroid system of keeping a stack of film, exposing the top and then ejecting it.

Motor Drive

Many cameras - particularly later ones - have some form of automated wind-on, triggered by the shutter release. These use a clockwork mechanism (e.g. the Robot cameras or the Kodak Instamatic X-45; see Category:Spring motor), or an electric motor. On a number of SLR systems produced between the 1960s and 1990s, add-on motor film-advance devices were available (winders usually capable of around two frames/second, and motor drives capable of around ten frames/second).